In October, Terry Thompson cut open the cages of dozens of the exotic animals—including tigers, lions, wolves, and bears—that he kept on his property outside Zanesville, Ohio. Then he committed suicide. Neighbors noticed the free-roaming animals and called the police who, over the course of several hours, shot and killed 49 animals.

The slaughter made headlines around the world (scroll down for a news video), and brought to the forefront a stark fact: Ohio was one of a few states that had no restrictions on owning exotic animals. (States make their own rules regarding exotic pet ownership; under the federal Captive Wildlife Safety Act, big cats by and large can't be moved across state lines.)

That changed on Tuesday, when Governor John Kasich signed into law new restrictions that ban new ownership of large cats, bears, certain monkeys and reptiles, and other animals. Current owners have to meet conditions, including obtaining state permits and carrying liability insurance, in order to keep their animals. Lawmakers approved the law last month.

Kasich said Ohio officials found the lack of rules governing exotic animal ownership in the state was a problem beyond the county where Thompson had his farm. “Ohio really was the Wild, Wild West,” Kasich told a news conference. “We had virtually no rules and no regulations in terms of all this.”

Attempts to craft legislation to restrict ownership of the animals drew criticism from private owners as too tough and from animal rights activists as too weak. In the end, lawmakers compromised by removing some species of small monkeys and lemurs from the restricted list, and reducing the amount of insurance a private owner must carry.

In “The Pet Offensive,” Audubon’s Ted Williams takes an in-depth look at this rogue industry out of control, and finds that the wild-pet business endangers not only people but also entire species by spreading disease, destroying habitat, and fueling hostility toward nature.